Bypass and demand pump and valve system for bypass and demand pump

Abstract

A diaphragm pump such as a three-chamber diaphragm pump includes a head having an inlet port and an outlet port and defining an inlet side including inlet chambers; and an outlet side having a center outlet chamber. Each of the inlet chambers includes an associated inlet valve. A single shutoff valve controlling fluid flow to the center outlet chamber and a single bypass valve in fluid communication between the center outlet chamber and the inlet side. The single shutoff valve has a plunger with an oval cross-section extending into the center outlet chamber. The single shutoff valve and the single bypass valve have adjustable pressure set points that are adjustable independently of one another.

What is claimed is: 
     
         1 . A diaphragm pump comprising:
 a head comprising an inlet port and an outlet port and defining an inlet side including a plurality of inlet chambers; and an outlet side having a center outlet chamber intermediate the plurality of chambers;   a plurality of inlet valves, wherein each of the inlet chambers includes an associated inlet valve;   a single shutoff valve controlling fluid flow to the center outlet chamber;   a single bypass valve in fluid communication between the center outlet chamber and the inlet side.   
     
     
         2 . A diaphragm pump according to  claim 1 , the single shutoff valve comprising a plunger extending into the center outlet chamber. 
     
     
         3 . A diaphragm pump according to  claim 2 , wherein the plunger comprises an oval cross section. 
     
     
         4 . A diaphragm pump according to  claim 1 , wherein the plunger comprises a stem, the stem including a recess receiving a spring. 
     
     
         5 . A diaphragm pump according to  claim 1 , wherein the plunger comprises a head with an oval cross section and a stem connected to the head, the stem including a recess receiving a spring. 
     
     
         6 . A diaphragm pump according to  claim 1 , wherein the single shutoff valve and the single bypass valve have adjustable pressure set points. 
     
     
         7 . A diaphragm pump according to  claim 6 , wherein the pressure set points are independently adjustable. 
     
     
         9 . A diaphragm pump according to  claim 1 , wherein the pump comprises three inlet chambers. 
     
     
         10 . A diaphragm pump according to  claim 1 , wherein head comprises three inlet chambers arranged in a triangular configuration with the central outlet chamber intermediate the three inlet chambers. 
     
     
         11 . A diaphragm pump according to  claim 1 , further comprising a wobbler device actuating the inlet valves. 
     
     
         12 . A diaphragm pump according to  claim 1 , comprising a single shutoff switch. 
     
     
         13 . A diaphragm pump system comprising:
 a head having a modular upper housing assembly, the modular housing assembly comprising:
 a first interchangeable upper housing assembly configured for operation of the pump system solely as a demand pump; 
 a second interchangeable upper housing assembly configured for operation of the pump system solely as a bypass pump; 
 a third interchangeable upper housing assembly configured for operation of the pump system as a demand pump or as a bypass pump. 
   
     
     
         14 . A diaphragm pump system according to  claim 13 , wherein each of the interchangeable upper housing assemblies includes three chambers in a triangular configuration and a central outlet chamber intermediate the three chambers. 
     
     
         15 . A method for making an upper housing of a diaphragm pump, the method comprising:
 molding using a first mold for creating a first interchangeable housing; or   molding with the first mold and a first insert for creating a second interchangeable housing; or   molding with the first mold and a second insert different from the first insert for creating a second interchangeable housing.   
     
     
         16 . A method according to  claim 15 , comprising adding a switch to the diaphragm pump housing created with only the first mold. 
     
     
         17 . A method according to  claim 15 , comprising adding an attachment to the diaphragm pump housing created with the first mold and the first insert. 
     
     
         18 . A method of operating a diaphragm pump as a demand pump and as a bypass pump, the diaphragm pump comprising:
 a head comprising an inlet port and an outlet port and defining an inlet side including a plurality of inlet chambers; and an outlet side having a center outlet chamber intermediate the plurality of chambers;   a plurality of inlet valves, wherein each of the inlet chambers includes an associated inlet valve;   a single shutoff valve controlling fluid flow to the center outlet chamber;   a single bypass valve in fluid communication between the center outlet chamber and the inlet side; the method comprising:   setting the single shutoff valve to a predetermined shutoff pressure; and   setting the single bypass valve to a predetermined bypass pressure.   
     
     
         19 . A method of operating a diaphragm pump as a demand pump and as a bypass pump according to  claim 18 , wherein the bypass pressure is greater than the shutoff pressure. 
     
     
         20 . A method of operating a diaphragm pump as a demand pump and as a bypass pump according to  claim 18 , wherein the bypass pressure and shutoff pressure are independently adjustable. 
     
     
         21 . A method of operating a diaphragm pump as a demand pump and as a bypass pump according to  claim 18 , wherein the bypass pressure and shutoff pressure are independently adjustable from an exterior of the pump. 
     
     
         22 . A head for a diaphragm pump; the head comprising:
 an inlet port and an outlet port and defining an inlet side including a plurality of inlet chambers; and an outlet side having a center outlet chamber intermediate the plurality of chambers;   a plurality of inlet valves, wherein each of the inlet chambers includes an associated inlet valve;   a single shutoff valve controlling fluid flow to the center outlet chamber;   a single bypass valve in fluid communication between the center outlet chamber and the inlet side.